Most personal computers spend more time idle than active, so researchers are harnessing their latent processing power with "distributed computing." In this model, a computer connected to the Internet performs a task and then sends the result back to a central server for analysis (see "Five Patents to Watch: Collective Computing," TR May 2001). It's an extremely powerful way to, say, sort through vast amounts of information looking for signs of alien life. But distributed strategies can't handle complex calculations, which require teamwork: each PC must crunch its own data, swap results with the others and repeat the process hundreds or thousands of times. All those computers talking at once slows the calculations-and the Internet-to a crawl.

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